Reland of Add a webrtc{en,de}coderfactory implementation for VideoToolbox

webrtc/modules/video_coding/codecs/h264/h264.cc

 /*
  *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  *
  */
 
 #include "webrtc/modules/video_coding/codecs/h264/include/h264.h"
 
 #if defined(WEBRTC_USE_H264)
 #include "webrtc/modules/video_coding/codecs/h264/h264_decoder_impl.h"
 #include "webrtc/modules/video_coding/codecs/h264/h264_encoder_impl.h"
 #endif
-#if defined(WEBRTC_IOS)
-#include "webrtc/modules/video_coding/codecs/h264/h264_video_toolbox_decoder.h"
-#include "webrtc/modules/video_coding/codecs/h264/h264_video_toolbox_encoder.h"
-#endif
 
 #include "webrtc/base/checks.h"
 #include "webrtc/base/logging.h"
 
 namespace webrtc {
 
 namespace {
 
 #if defined(WEBRTC_USE_H264)
 bool g_rtc_use_h264 = true;
 #endif
 
 }  // namespace
 
 void DisableRtcUseH264() {
 #if defined(WEBRTC_USE_H264)
   g_rtc_use_h264 = false;
 #endif
 }
 
-// We need this file to be C++ only so it will compile properly for all
-// platforms. In order to write ObjC specific implementations we use private
-// externs. This function is defined in h264.mm.
-#if defined(WEBRTC_IOS)
-extern bool IsH264CodecSupportedObjC();
-#endif
-
 // If any H.264 codec is supported (iOS HW or OpenH264/FFmpeg).
 bool IsH264CodecSupported() {
-#if defined(WEBRTC_IOS) && defined(WEBRTC_VIDEO_TOOLBOX_SUPPORTED)
-  if (IsH264CodecSupportedObjC()) {
-    return true;
-  }
-#endif
 #if defined(WEBRTC_USE_H264)
   return g_rtc_use_h264;
 #else
   return false;
 #endif
 }
 
 H264Encoder* H264Encoder::Create() {
   RTC_DCHECK(H264Encoder::IsSupported());
-#if defined(WEBRTC_IOS) && defined(WEBRTC_VIDEO_TOOLBOX_SUPPORTED)
-  if (IsH264CodecSupportedObjC()) {
-    LOG(LS_INFO) << "Creating H264VideoToolboxEncoder.";
-    return new H264VideoToolboxEncoder();
-  }
-#endif
 #if defined(WEBRTC_USE_H264)
   RTC_CHECK(g_rtc_use_h264);
   LOG(LS_INFO) << "Creating H264EncoderImpl.";
   return new H264EncoderImpl();
 #else
   RTC_NOTREACHED();
   return nullptr;
 #endif
 }
 
 bool H264Encoder::IsSupported() {
   return IsH264CodecSupported();
 }
 
 H264Decoder* H264Decoder::Create() {
   RTC_DCHECK(H264Decoder::IsSupported());
-#if defined(WEBRTC_IOS) && defined(WEBRTC_VIDEO_TOOLBOX_SUPPORTED)
-  if (IsH264CodecSupportedObjC()) {
-    LOG(LS_INFO) << "Creating H264VideoToolboxDecoder.";
-    return new H264VideoToolboxDecoder();
-  }
-#endif
 #if defined(WEBRTC_USE_H264)
   RTC_CHECK(g_rtc_use_h264);
   LOG(LS_INFO) << "Creating H264DecoderImpl.";
   return new H264DecoderImpl();
 #else
   RTC_NOTREACHED();
   return nullptr;
 #endif
 }
 
 bool H264Decoder::IsSupported() {
   return IsH264CodecSupported();
 }
 
 }  // namespace webrtc